Printer control system



Oct. 17, 1967 1 M. p. TUBINIS 3,348,212

PRINTER CONTROL SYSTEM S 2 lL /NVENTOR MATTHEW P. TUBINIS A TTORNE YS Oct. 17, 1967 f M. P. TUBlNls 3,348,212

PRINTER CONTROL SYSTEM Filed Dec. 18. 1964 5 Sheets-Sheet 2 /N VEN TOR MATTHEW P. TUB|N|S my l.,

A T ORNEYS l M. P. TUBINIS PRINTER CONTROL SYSTEM Oct. 17, 1967 3 Sheets-Sheet 5 Filed DSC. 18. 1964 OQ .,o4

IIIIIJL /NVEA/rof? E MATTHEW P. TUBINIS By j Arromvfrs United States Patent O 3,348,212 PRINTER CONTROL SYSTEM Matthew P. Tubinis, Pentield, N.Y., assigner to Xerox Corporation, Rochester, N.Y., a corporation of New York Filed Dec. 18, 1964, Ser. No. 419,391 7 Claims. (Cl. S40-172.5)

ABSTRACT F THE DISCLDSURE This invention relates to high speed printing apparatus and, in particular, to a control system for high speed printers of the type used to print information from electrical signals received from a computer or other external source.

A type of printer suitable for use with the control systcm described herein consists of an array of columns and rows of printing elements or characters arranged in a position to act upon the surface of an image receiving member. The columns extend in the direction of movement of the image receiving member and contain a printing element of each of the characters to be printed. The rows of printing elements extend transversely to the direction of movement of the image receiving member and contain printing elements of only one character to be printed. There are as many rows as there are characters to be printed and there are as many columns as there are printing spaces in a printed line on the image receiving member.

In this type of printer the input signals, representing characters to be printed, are fed to appropriate elements in the particular row and column by means of a control system. The control system provides a time delay for the signals of each character until the image receiving member is in position beneath the row corresponding to that character, and further positions the character in its proper location across the printed row.

Conventional line printers usually consist of a series of rotating discs, reciprocating bars, moving chains or other means containing the full range of characters to be printed. This type of printer presents all characters to be printed to a single print position for actuation in response to the electrical signal input. Whereas line printers print each line sequentially as signals are received from the computer; the printing in the type of matrix printer shown herein is performed on a plurality of lines at the same time.

The present invention is a control system useable with the matrix type printer. Prior control systems for this type printer involved complex electronic equipment. Applicants invention is a relatively simple device which has the flexibility of being adaptable to various size printers. That is, it may be used with printers having a various number of characters or symbols to be printed, and it is useable for printing a copy that has various character positions per line.

It is the primary object of this invention to improve control systems for high speed printing apparatus of the type capable of being operated from electrical signal input.

It is a further object of this invention to improve con- 3,348,212 Patented Oct. 17, 1967 ICC trol systems for matrix type printers to eliminate the use of electronic equipment.

Further objects of this invention are to provide a relatively small, incxpcnsive and reliable control system for use with high speed printers.

These and other objects of the invention are attained by means of a control system wherein electrical signals, corresponding to characters to be printed, are temporarily stored in line-by-line sequence so that the signals of a number of lines may be read simultaneously in `timed relation to the position of each signal in the printed line and to thereby actuate appropriate elements in each row in timed relation to the electrical signal input.

For a better understanding of the invention as well as other objects and further features thereof, reference is had to the following detailed description of the invention to bc read in connection with the accompanying drawings, wherein:

FIG. 1 is a schematic representation of a printer control system embodying the invention and utilizing a magnetic drum storage device;

FIG. 2 is an isometric representation of a xerographic printer suitable for use with the control system shown in FIG. l; and,

FIG. 3 is a schematic representation of an alternative embodiment of a control system utilizing a magnetic tape storage device.

A xerographic printer containing an array of printing elements suitable for use with `the control system disclosed herein is shown in FIG. 2. The printer is of the type wherein electrostatic images are formed on the surface of a dielectric image receiving member 12. The image receiving member 12 is in the form of a web of material such as Mylar, paper or any other dielectric substance having a sutiiciently high resistance to hold an electrostatic image for a period which permits subsequent utilizing of the image by a transfer to another surface, or by development thereof. The formation of the electrostatic latent image on the image receiving member is performed at a printing station 14, and the image receiving member is advanced in the direction indicated by the arrows in FIGURE 2 to a developng station 16 wherein the electrostatic images are developed with a liquid or powdered toner material to produce visible images of the characters being printed. The developed images are fused or bonded to the surface of the image receiving member at fusing station 18 by means of any suitable type of fusing apparatus such as the heated pressure roller 20, shown herein.

At the print station 14 there is an arrangement of printing elements or electrodes 24 mounted on a template 22. The printing elements 24 consist of raised metal characters resembling type faces of characters to be printed. The character faces are positioned closely adjacent to the image receiving member 12 but spaced therefrom. Each of the characters of the printing elements constitute a printing electrode and are electrically connected to each of the other printing elements in the same column and are electrically insulated from each of the elements in the same row. The arrangement of the printing elements over the surface of the image receiving member 12 is such that rows containing printing elements of one character extend transversely to the direction of movement of the web 12 and colums containing printing elements representative of each character to be printed extend in the direction of movement of the web. Beneath the template 22 on the opposite side of, and in contact with, the web 12 there is a second series of electrodes 26 in the form of bars extending across the web 12. When the electrodes 24 and 26 are subjected to a voltage differential of sucient intensity and electrostatic discharge from the printing electrodes 24 will impart an electrostatic charge in character configuration upon the surface of the image receiving member. For purposes of illustration, assuming that the threshold voltage with the printing elements used herein is in excess of 1,000 volts but less than 2,000 volts so that when 1,000 volts is impressed across the electrodes an electrostatic discharge does not take place; but when the same elements are pulsed with a second 1,000 volts to produce 2,00() volt differential, the electrostatic discharge will take place and an image will be formed on the web 12.

In the schematic representation in FIGS. 1 and 2, the printing elements 24 are shown as characters on the top of the template 22. This representation is used only for the purpose of indicating which characters are being printed at a given position. The actual character formed on the printing element is on the underneath side of the template 22 adjacent to the web 12.

It can be seen from FIG. l that when a complete group of electrical signals representing a single printed line has been received by the printer all the characters of one type in that line may be printed by the first row of characters 24, and if the other characters are delayed a length of time sufficient for the web to travel to a position corresponding to that character in the matrix then each character may be printed in the same line at different times. That is, all the As in the first line are printed sequentially during time one; and as the web advances one space, the Bs in that line could be printed in time two; and upon subsequent movement of the web, each f the characters could be printed in that line in timed relation to its character position in the colums. Also at time two when the Bs are being printed in line one all the As from a set of signals corresponding to the seco-nd printed line could be printed in line two. Following this pattern, it would be possible to simultaneously print, at time three, all the Cs in line one, Bs in line two, and As in line three. Thus, when the first line has been completely printed and emerges from beneath the template 22, the printer would be printing all the rows of charactrs in different lines at each time interval.

The selection of each printing element is accomplished by serially pulsing each column of elements 24 with a voltage less than the threshold voltage, for example, 1,000 volts. This voltage is impressed on the common lead to each of the printing elements in a column by means of a counter and pulse generator 28. Any character in that column may be actuated by impressing a second 1,000 volt pulse of opposite polarity upon electrode 26 corresponding to the row to be printed. The differential voltage at the printing element common to the pulsed column and pulsed row exceeds the threshold voltage of the printing elements and thus impresses an electrostatic charge pattern on the web. By serially pulsing each column and selective pulsing the rows in response to control signals, selected printing elements will be actuated according to the electrical signal input.

In the embodiment shown in FIGURE l electrical signals are received from an external source such as a computer through line 30 and amplifier 31 to a temporary storage device such as magnetic drum 32. The line 3l] is connected to a write head 34 which magnetically stores the information in the first track of a set of tracks on the magnetic drum. As the drum rotates, the information in the first track is acted upon by subsequent read heads around the drum, then erased from track one and stored in track two. On each revolution of the drum all information is moved down one track and new signals are placed in track one. The drum is sized to store sets of signals corresponding to lines of printing at least equal in number to the number of different characters in the printer or equal to the number of rows of printing elements.

If for purposes of illustration it is assumed that the printer is composed of 51 different characters to be printed and thus has 51 rows of printing elements then the magnetic drum is sized to store 51 lines of information. The drum shown in FIG. 1 is capable of storing three lines of information on each track around the drum surface and the drum has 17 such storage tracks and one timing track 35. There are three groupings of read heads, indicated at 36, 38 and 40, equally spaced around the drum with each group containing 17 read heads or one read head per track. The distance between the write heads 34 and the read heads 36 is exactly one line of information. For example, if the printed line contains character positions and the information is received serially in a six bit code, then the spacing between the write head and the first read head would be 720 bits of in formation. Likewise, if the electrical signals are received in parallel, then the spacing would be equal to 120 bits of information with six read heads at each station. The read heads 38 are also spaced from the read heads 36 and 40 by one line of information.

When the information placed in the first track by the first write head 34 is read by the first read head 40, it is erased and fed through line 42 to amplifier 40 where it is fed to the second write head 34 for storage in the second track. This process is repeated for each revolution of the drum and the information is fed down to the last track at which time it is merely erased by the last read head 40.

As the information is read by the read heads 36, 38 and 40, the information is transmitted through lines 46 to a series of amplifiers 48 then through a timing gate 49 to a series of decoders and pulse generators 50. The decoders and pulse generators are well known in the art and do not require detailed description herein. However, it should be noted that each decoder and pulse generator is set to respond to one of the characters to be printed. For example, the decoder and pulse generator 50 which receives signals from the read head 36 on the first track is shown herein as set to generate a pulse only upon the receipt of signals corresponding to the character A; the decoder and pulse generator attached to the lead head 38 in the first track is set to generate a pulse upon receipt of information corresponding to the letter B; and the decoder and pulse generator receiving information from the read head 40 in the first track is set to generate a pulse upon the detection of information corresponding to the letter C. This series is continued for each read head, that is, the decoder and pulse generator receiving information from the read head 36 in the second track is set to gener ate a pulse upon receipt of information corresponding to the letter D and the decoder and pulse generator receiving information from the read head 4t) in the last track on the magnetic drum is set to generate a pulse upon receipt of information corresponding to the numeral 0.

The timing track 35 on the drum 32 has information recorded thereon to control the counter and pulse generator 28. A clock read head S2 reads the information on the clock track and supplies the information to the counter and pulse generator 28 so that the columns in the printer are pulsed sequentially in timed relation to the movement of the drum 32. The signal from the clock read head 52 is also used to control the drive system, not shown, of the web or image receiving member 12. Thus the web 12 is moved past the printing elements 24 at a speed synchronized with the rotational speed of the drum 32.

In operation, signals received from an external source are printed by the first write head 34 in the first track of the drum. When the first bit of information on the `drum passes beneath the first read head 36 that information is transmitted to the decoder and pulse generator 50 corresponding to the character A. The decoder Will trigger a pulse across the first row in the printer if the information received corresponds to the letter A. At the same time the counter and pulse generator 28 is pulsing the first column in the printer. Thus, if an A is the first letter to be printed, then the counter and pulse generator would have pulsed the first column and the decoder and pulse generator would have pulsed the first row so that the letter A which is common to the first row and the first column would have been printed on the page. As the second letter is read by the first read head 36, the counter and pulse generator pulses the second column and the decoder and pulse generator 50 would either pulse or not pulse the first row depending on whether or not an A was detected. This process continues until the first read head 36 has read each character in the first line and the counter and pulse generator 28 has sequentially pulsed each column across the printer. At this time the second line of information received from the computer had been Written into the first track by the first write head 34 and the first read head in the group 38 is about to read the first character in the first line of information received and the first read head in the group of read heads indicated at 36 is about to read the rst character in the second line of information. The first read head in group 38 passes its information to the decoder and pulse generator 50 corresponding to the second row or the letter B at the same time that the first read head 36 is transmitting its information to the decoder and pulse generator 50 corresponding to the first row or the letter A. Thus, during this reading cycle, Bs are being printed in the first line and As are being printed in the second printed line. At the end of this cycle the first read head 40 is in a position to read the letters C in the rst line of information at the same time that the first read head in group 38 will be reading the Bs in the second line of information and the first read head 36 is reading the As in the third line of information. The read head 40, as pointed out above, not only transmits the information to the decoder and pulse generator corresponding to the letter C but also transmits the information to the second write head 34 for storage in the second track on the drum 32. The information is now erased from the first track of the drum so that it does not interfere with subsequent information being received by the first write head. This process is repeated as information is received until all read heads in the groups 36, 38 and 40 are reading information simultaneously and transmitting it to the decoder and pulse generators 50. Thus, for any given pulse by the counter and pulse generator 28 any number of the characters in a column may be printed.

The web 12 may be stepped a line at a time corresponding to a complete cycle of the counter and pulse generator 28, that is, in timed relation to each line of informa` tion received from the external source. However, the speed of printing with this type of apparatus is such that the web 12 can be operated continuously in timed relation to the movement of the magnetic drum. If, due to the continuous movement of the web, the information is not being printed exactly on line, then the printing elements 24 may be skewed slightly to compensate for the continuous movement of the web.

The second embodiment of the control system is shown in FIG. 3 and utilizes a magnetic tape as a temporary storage device rather than a magnetic drum. This system eliminates the need for additional write heads once the information is placed on the tape.

Information is received from an external source, such as a computer, through line 56 and amplifier 58. The signals are impressed on a magnetic tape 60 in sets of signals corresponding to a printed line by means of a write head 62. There are a set of read heads 64 corresponding in number to the different characters to be printed or the number of rows of printing elements. The `read heads 64 are spaced along the tape 60 in a manner similar to the spacing of the read heads on the magnetic drum. That is, the distance between the write head 62 and the first read head 64 `and between each of the read heads 64 is exactly the distance required to store one set of signals corresponding to a printed line.

The magnetic tape 60, as shown herein, is in the form of a continuous loop wherein the tape after passing the last read head 64 continues around past an erasure station -66 to the write head 62. The information stored on the tape is erased at the erasure station 66 so that new information may be placed on the tape by the write head 62.

Each of the read heads 64 is connected to a decoder and pulse generator 68 which in turn are attached to the common leads of the rows of printing elements as described for the embodiment shown in FIG. l. Each decoder and pulse generator is set to be actuated upon detection of a different character so that the row of printing elements of that character are pulsed in response to electrical signals.

A counter and pulse generator 70 is operatively connected to a `read head 72 which continuously senses a timing track on the tape 60. The counter and pulse generator 70 is connected to the common leads of each of the columns of printing elements and sequentially pulses each of the columns in response to the signals received from the timing track on the tape 60. The counter and pulse generator also controls the drive mechanism for moving the image receiving member past the printing elements, so that the image receiving member is advanced at a rate consistent with the detection of signals stored on the magnetic tape 60.

As the counter and pulse generator 70 pulse the first column of printing elements each of the read heads 64 senses the first character in the particular line that it is reading from the magnetic tape. If appropriate signals are received by the decoders and pulse generators 68 the electrodes corresponding to those decoders and pulse generators are also pulsed and various printing elements in the rst column are actuated. The counter and pulse generator then pulse the second column and the read heads 64 read the second signal in the line and pulse the appropriate rows. This process is continued until each column has been pulsed and sets of signals corresponding to printed lines have passed beneath each read head 64 at which time the counter and pulse generator again pulses the first column and the read heads 64 read the first signals in the next set of signals. Between each pulsing of the first column the image receiving member 12 is advanced a distance equal to one line.

It is also within the scope of this invention, to feed the incoming signals into electrical delay lines which are read at various points along the line to provide the control necessary to the operation of this type of printer. The delay lines would be used in place of the magnetic drum or magnetic tape.

While the invention has been described with reference to the structure disclosed herein, it is not confined to the details set forth, and this application is intended to cover such modifications or changes as may come within the purposes of the improvements or the scope of the following claims.

What is claimed is:

1. Apparatus for controlling a printer in response to electrical signals, the printer being of the type wherein an image receiving member is moved past an array of printing elements, the elements being arranged in columns and rows with each column extending in the direction of movement of the image receiving member and having elements representing each of the characters to be printed and each row extending transversely to the direction of movement of the image receiving member and having elements representing one of the characters to be printed, including:

storage means to store signals received according to their column position in a printed line, the storage means being arranged in tracks and being of a size sufficient to store signals representing a number of printed lines equal to the number of rows of printing elements,

means operatively associated with said storage means for transposing the signals received in each track to the next adjacent track,

signal detecting means operatively associated with the storage means to simultaneously detect all signals in the same column position in the storage means and to detect each column sequentially,

and means operatively associated with the detecting means to determine the presence of pre-determined signals in the storage means and to actuate the elements in the proper columns and rows of the printer according to the column being detected and the rows represented by the signals detected.

2. Apparatus for controlling a printer in response to electrical signals, the printer being of the type wherein an image receiving member is moved past an array of printing elements, thc elements being arranged in columns and rows with each column extending in the direction of movement of the image receiving member and having elements representing each of the characters to be printed and each row extending transversely to the direction of movement of the image receiving member and having elements representing one of the characters to be printed, including:

means to store sets of signals representing characters to be printed in a line with each signal stored in a predetermined relationship to the position of the character in the printed line,

said storage means having an array of tracks of a capacity sufiicient to store a number of sets of signals equal to the number of rows of printing elements,

means operatively associated with the storage means for transposing the signals received in each track to the next adjacent track,

signal detecting and decoding means operatively associated with the storage means to sequentially read and decode each signal in the sets of signals stored, there being as many detecting and decoding means as there are rows of printing elements,

means to actuate printing elements in each row in response to signals from the detecting and decoding means in timed relation to the line position of the signal detected,

and means to control the movement of the image receiving member relative to the rate of detection of signals in the storage means. 3. Apparatus for controlling a printer in response to electrical signals, the printer being of the type wherein an image receiving member is moved past an array of printing elements, the elements being arranged in columns and rows with cach column extending in the direction of movement of the image receiving member and having elements representing each of the characters to be printed and each row extending transversely to the direction of movement of the image receiving member and having elements representing one of the characters to be printed, including:

a rotatable magnetic drum adapted to store electrical signals serially received from an external source,

means to place the electrical signals on the surface of the magnetic drum in timed sequence according to the column position of the character represented by the electrical signal, the drum having tracks arranged therein and being of sufficient size to store electrical signals corresponding to the characters to be printed in a number of lines equal to the number of rows of printing elements, signal reading means associated with the magnetic drum to simultaneously read all the signals of a column position in each line of stored signals,

means operatively associated with the drum for transposing the signals received in each track to the next adjacent track,

decoding and pulse generating means connected to each dll fili

row of elements to pulse the row of elements upon detection of a character corresponding to that row by the signal reading means,

means synchronized with the movement of the magnetic drum to pulse each column of elements as the reading means reads the electrical signals corresponding to that column position,

the pulse imposed on the rows of elements and on the columns of elements being insucient individually to actuate the elements and being sufficient jointly to actuate the elements whereby elements common to a pulsed column and a pulsed row are actuated,

and means to control the movement of the image receiving member in timed relation to the rotation of the magnetic drum.

4. Apparatus for controlling a printer in response to electrical signals, the printer being of the type wherein an image receiving member is moved past an array of printing elements, the elements being arranged in columns and rows with each column extending in the direction of movement of the image receiving member and having elements representing each of the characters to be printed and each row extending transversely to the direction of movement of the image receiving member and having elements representing one of the characters to be printed, including:

a rotatable magnetic drum adapted to store electrical signals serially received from an external source in tracks around the drum surface,

means to impose electrical signals on the drum surface in a first track as they are received from an external source,

means to impose each of the signals in the tracks on the next succeeding track as the magnetic drum rotates,

means to remove the signals in the last track from the magnetic drum,

a plurality of read heads positioned around the tracks of the magnetic drum to simultaneously read all the electrical signals representing characters to be printed in a given column,

means responsive to the rotation of the magnetic drum to sequentially permit all the elements in each column to be actuated as the read heads detect the stored signals corresponding to the characters to be printed by that column,

and decoders and pulse generators associated with each of the read heads to actuate the elements in the column being detected by the read heads when the signals detected correspond to a predetermined signal for each of the decoders,

and means responsive to rotation of the magnetic drum to control the movement of the image receiving member past the printing elements.

5. Apparatus for controlling a printer in response to electrical signals, the printer being of the type wherein an image receiving member is moved past an array of printing elements, the elements being arranged in columns and rows with each column extending in the direction of movement of the image receiving member and having elements representing each of the characters to be printed and each row extending transversely to the direction of movement of the image receiving member and having elements representing one of the characters to be printed, including:

magnetic tape storing means adapted to receive and store signals from an external source in timed sequence to the receipt of such signals,

said tape being of sufficient size to store sets of electrical signals corresponding to lines to be printed of a number equal to the number of rows of printing elements,

a number of read heads equal to the number of rows of printing elements positioned relative to the magnetic tape to simultaneously detect all the signals of a column position in each of the sets of signals printed lines corresponding to the number of rows of stored, printing elements,

means operable in timed relation to the detection of and means to decode the signals read from the surface stored signals to sequentially energize each column of the magnetic drum of each row and to energize of elements to a level whereby they will be actuated the printing elements in the row corresponding to by a subsequent pulse, the character decoded and in the column indicated a signal decoder and a pulse generator associated with by the time position ofthe electrical signal in the line each of the read heads and each of the rows of eleof information stored on the magnetic drum.

ments whereby upon detection of a predetermined 7. Apparatus for controlling a matrix printer from elecsignal by the read head a pulse will be generated to l trical signals representing characters to be printed inactuate the printing element in the associated row cluding:

and in the column being energized, means including tracks arranged side by side adapted and means to control the movement of the image refor movement to store all signals in a timed sequence ceiving member past the printing elements in timed for a plurality of lines to be printed, the signals rerelation to the detection of signals on the magnetic ceived on each track being transposed to an adjacent tape. track,

6. Apparatus for controlling a plurality of printing elemeans to read simultaneously signals in print position, ments arranged in columns and rows in a position to print means to detect and decode predetermined signals read upon an image receiving member wherein the columns by the reading means, contain printing elements of each of the characters to be and means to actuate the printer in accordance with printed and the different rows contain printing elements the signal detected and decoded and the timed ocot one of the characters to be printed, including: curence at the signal.

means to move the image receiving member past the printing elements in a predetermined time sequence, References Cited a magnetic drum having a plurality of write heads adapted to place electrical signals in tracks on the UNITED STATES PATENTS magnetic drum as the drum is rotated whereby 3.182,333 5/1955 Amada et aL 34(5 74 signals received in each track can be transposed to the next adjaCent traCk in Spllllllke fahln, ROBERT C. BAILEY, Primary Examner a plurality of read heads arranged relative to the drum to simultaneously read the signals of a number of G. D. SHAW, Assistant Examiner. 

1. APPARATUS FOR CONTROLLING A PRINTER IN RESPONSE TO ELECTRICAL SIGNALS, THE PRINTER BEING OF THE TYPE WHEREIN AN IMAGE RECEIVING MEMBER IS MOVED PAST AN ARRAY OF PRINTING ELEMENTS, THE ELEMENTS BEING ARRANGED IN COLUMNS AND ROWS WITH EACH COLUMN EXTENDING IN THE DIRECTION OF MOVEMENT OF THE IMAGE RECEIVING MEMBER AND HAVING ELEMENTS REPRESENTING EACH OF THE CHARACTERS TO BE PRINTED AND EACH ROW EXTENDING TRANSVERSELY TO THE DIRECTION OF MOVEMENT OF THE IMAGE RECEIVING MEMBER AND HAVING ELEMENTS REPRESENTING ONE OF THE CHARACTERS TO BE PRINTED, INCLUDING: STORAGE MEANS TO STORE SIGNALS RECEIVED ACCORDING TO THEIR COLUMN POSITION IN A PRINTED LINE, THE STORAGE MEANS BEING ARRANGED IN TRACKS AND BEING OF A SIZE SUFFICIENT TO STORE SIGNALS REPRESENTING A NUMBER OF PRINTED LINES EQUAL TO THE NUMBER OF ROWS OF PRINTING ELEMENTS, MEANS OPERATIVELY ASSOCIATED WITH SAID STORAGE MEANS FOR TRANSPOSING THE SIGNALS RECEIVED IN EACH TRACK TO THE NEXT ADJACENT TRACK, SIGNAL DETECTING MEANS OPERATIVELY ASSOCIATED WITH THE STORAGE MEANS TO SIMULTANEOUSLY DETECT ALL SIGNALS IN THE SAME COLUMN POSITION IN THE STORAGE MEANS AND TO DETECT EACH COLUMN SEQUENTIALLY, AND MEANS OPERATIVELY ASSOCIATED WITH THE DETECTING MEANS TO DETERMINE THE PRESENCE OF PRE-DETERMINED SIGNALS IN THE STORAGE MEANS AND TO ACTUATE THE ELEMENTS IN THE PROPER COLUMNS AND ROWS OF THE PRINTER ACCORDING TO THE COLUMN BEING DETECTED AND THE ROWS REPRESENTED BY THE SIGNALS DETECTED. 